Neverwhere

A man in London encounters an injured young woman, and instantly exists only to those in London Below. As he helps the woman escape from assassins, he must try to find his way back to London Above.

Neverwhere is a 1996 drama mystery movie, starring Gary Bakewell, Hywel Bennett, Laura Fraser. It holds an IMDb rating of 7.2/10 from 3,235 votes and runs 30m.